Well it is a crime to use it for obscuring illegal money, while it is not illegal to use Tor for obscuring illegal internet traffic

In both situations using it for legal purposes is legal.

But the ‘illegal’ scenario is different as money laundering is a crime on its own, while “laundering internet traffic” is not a crime.

It’s a bit like a pharmacy that also dispenses heroin to kids - it doesn’t matter that the legal drugs are being sold, selling crack to kids is illegal by itself.